Potential screening strategies for early prediction of pre-eclampsia

Background: This study was conducted to evaluate the efficacy of different biochemical and biophysical markers in the early weeks of gestation as screening tools for early prediction of preeclampsia.Methods: This hospital-based prospective observational study conducted on 52 pregnant women, at less than 13 weeks of gestation were recruited. Maternal serum inhibin A and USG uterine artery PI levels were analyzed among the pregnant women who subsequently developed PE and compare with those who did not develop PE. Methods used for the detection of markers were: chemiluminescence immunoassay (CLIA) for serum inhibin A levels, and uterine artery Doppler velocimetry was done by PHILIPS HD11XE transabdominal ultrasound machine using a 4-6 MHz probe with the same sonographer.Results: The present study revealed a significant rise of inhibin A in preeclamptic women when compared to normotensive women (p<0.0001). The mean levels of 1st and 2nd trimester uterine artery PI significantly high in women who subsequently developed PE when compared to those who did not develop preeclampsia (p<0.0001). Study results showed a strong association between gestational age at delivery and neonatal outcome (neonatal birth weight and APGAR) with preeclampsia. The maternal serum inhibin A, and uterine artery PI found to have good sensitivity and specificity for early prediction of PE.Conclusions: Study concluded that the women who are prone to develop PE subsequently, had high levels of MAP, UAPI, inhibin A. In our setting, MAP, UAPI, inhibin A, appeared to be better screening modalities. Combination of the biochemical markers with the biophysical markers, demographic characteristics, and other novel markers will establish the effective screening models for early prediction of PE. Early identification of high-risk cases will offer an opportunity for prophylactic therapy, such as Low- dose Aspirin in selected groups of high-risk women screened in the first trimester, thus improving the maternal and perinatal outcome

Language endangerment and language documentation in Africa

Non peer reviewe

Profiles, Preferences, and Reactions to Price Changes of Bikeshare Users: A Comprehensive Look at Capital Bikeshare Data

In the decade since 2007, public bikeshare systems (PBS) have disrupted the landscape of urban transportation systems all over the world. The rapid pace at which urban systems are enduring this disruption due to PBS has left cities and researchers play catch up on understanding various factors impacting the usage and impacts of PBS. Comprehending the profiles and preferences of bikeshare users have a substantial role to play in policy-making, planning and operational management at PBS. However, the research is scant related to these factors. As its first major objective, this research evaluated the impact of pricing on bikeshare ridership and revenue. As a case study, the introduction of single-trip fare (STF) for $2 by Capital Bikeshare (CaBi) was studied. Aggregate analysis results showed that the first-time casual (short-term) users increased by as much as 79% immediately after the introduction of STF. Jurisdiction-level analysis indicated a statistically significant increase in casual user ridership for identical 12-month periods before and after the introduction of STF. The introduction of STF did not impact ridership and revenues of registered (annual or monthly) members. Casual user revenues before and after the introduction of STF were also compared at the station-level, while controlling seasonal and weather factors. The results showed a statistically significant increase in ridership and decrease in revenue per ride for casual users after the introduction of STF. Even though casual bikeshare users account for a large share of revenue, literature provides very little insights about the casual users. As the second major objective of this research, profiles and preferences of bikeshare users (registered members and casual users) were obtained by conducting an intercept survey of CaBi users. Survey findings indicated that, when compared to casual users, registered members are more likely to earn more and are more sensitive to service as reflected by station density. A typical White user has 2.4 times greater odds of being registered members than other race. Analysis also revealed that each additional increase in the number of monthly trips leads to about 18% increase in the odds of the bikeshare user being a registered member. As the third major objective, this research evaluated price sensitivities and elasticities of bikeshare fare products using monadic design implemented in the survey instrument. Higher household income groups and White users were found to be less sensitive to price compared to other income groups and other races/ethnicities. Pivot-price elasticities revealed that females are about 30% and 10% more price sensitive than males for single-trip fare (STF) and annual membership, respectively. Also, sightseeing trips are 30% less price sensitive than work trips for STF purchasers. Results from this study would be useful in policy-making, planning and operations for bikeshare systems

Technology assessment of renewable energy sustainability in South Africa

Thesis (PhD (School of Public Leadership))--University of Stellenbosch, 2012.Please download the required VENSIM software from: http://www.vensim.com/freedownload.htmlENGLISH ABSTRACT: Technology assessment has changed in nature over the last four decades. It changed from an analytical tool for technology evaluation, which depends heavily on quantitative and qualitative modelling methodologies, into a strategic planning tool for policy-making concerning acceptable new technologies, which depends on participative policy problem analysis. The goal of technology assessment today is to generate policy options for solutions of organisational and societal problems, which at the operational level, utilise new technologies that are publicly acceptable; that is, viable policy options. Energy technology assessment for sustainability is inherently a complex and dynamic process that requires a holistic and transdisciplinary approach. In the South Africa context, specifically, there is no formal and coherent approach to energy technology assessment from a sustainability perspective. Without a formal comprehensive or well integrated technology assessment approach to evaluate the sustainability of any technology, the policy-makers, technology designers, and decision-makers are faced with difficulty in terms of making reasoned decisions about the appropriate technology options. This study developed a framework that incorporates a technology assessment approach, namely, system dynamics, within the broader scope of technology development for sustainability. The framework, termed the Systems Approach to Technology Sustainability Assessment (SATSA), integrates three key elements: technology development, sustainable development, and a dynamic systems approach. The study then provides a guiding process of applying the framework to energy technology assessment theory and practice within the context of sustainable development. Biodiesel, a cleaner burning replacement fuel, argued to potentially contribute to sustainable development, is used for the demonstration. Biodiesel development entails complex interactions of actors such as the technology developers, government at different levels, communities, as well as the natural environment. Different actions or responses in the greater system might hinder or undermine the positive effects of such a development. Based on the SATSA framework, a Bioenergy Technology Sustainability Assessment (BIOTSA) model was developed. The BIOTSA model was used to test the outcomes of a proposed biodiesel production development in the Eastern Cape Province of South Africa on selected sustainability indicators. In addition, some policy scenarios were tested to compare how they assist in improving the selected indicators. The BIOTSA model results are useful in comparing dynamic consequences resulting from a proposed biodiesel production development and the respective policies and decisions that may arise from such a development. The testing and validation of the BIOTSA model was carried out based on structural validity, behavioural validity, and expert opinion. Potential policy scenario outcomes and their implication, on the selected sustainability indicators, were also tested. The opinions of the selected stakeholders indicated that the BIOTSA model was useful in providing an understanding of the potential impacts of the biodiesel development on selected sustainability indicators in the Eastern Cape Province. Thus, the SATSA framework can be applied for assessing sustainability of other renewable energy technologies. In addition, system dynamics provide a useful and a feasible dynamic systems approach for energy technology sustainability assessment. Finally, the model building process and transdisciplinary nature of this study enabled the identification of the potential problems that could arise during the biodiesel production development. In addition, gaps in data and knowledge were identified and the recommendation for future work in this field is highlighted. Nevertheless, the findings of the BIOTSA model could inform policy- and decision-making in biodiesel production development in South Africa. The development of similar models for other renewable energy development efforts is thus recommended. The current efforts to facilitate the large-scale roll out of concentrated solar thermal technologies in Southern Africa, for example, would require the development of a Solar Thermal Technology Sustainability Assessment (SOTTSA) model.AFRIKAANSE OPSOMMING: Die aard van tegnologie assessering het in die afgelope vier dekades verander. Dit het verander ten opsigte van ’n analitiese hulpmiddel vir tegnologie evaluering, wat hoofsaaklik staatmaak op kwalitatiewe en kwantitatiewe modelleringsmetodiek, na ’n strategiese beplanningshulpmiddel vir beleidvorming met betrekking tot nuwe aanvaarbare tegnologieë, wat afhanklik is van ’n deelnemende beleidsprobleem analise. Vandag se doel vir tegnologie assessering is om beleidsopsies vir oplossings van organisatoriese en sosiale probleme te genereer, wat op operasionele vlak gebruik maak van nuwe tegnologieë wat deur die publiek aanvaar is; met ander woorde, lewensvatbare beleidsopsies. Energie tegnologie assessering vir volhoubaarheid is sonder twyfel ’n komplekse en dinamiese proses wat ’n holistiese en transdisiplinêre benadering benodig. In die Suid- Afrikaanse konteks is daar geen formele en samehangende benadering tot tegnologie assessering vanaf ’n volhoubaarheidsperspektief nie. Beleidsmakers, tegnologie ontwerpers en besluitnemers mag sukkel om beredenerende besluite te neem oor die toepaslike tegnologie opsies sonder ’n formele omvattende of goed geïntegreerde tegnologie assesseringsbenadering om die volhoubaarheid van enige tegnologie te evalueer. Hierdie studie het ’n raamwerk ontwerp wat die tegnologie assesseringsbenadering inkorporeer binne die breë bestek van tegnologiese ontwikkeling vir volhoubaarheid naamlik, stelsel dinamika. Die raamwerk, genoem die Sisteem Benadering tot Tegnologie Volhoubaarheidsassessering (SBTVA) integreer drie sleutelelemente: tegnologiese ontwikkeling, volhoubaarheidsontwikkeling, en ʼn dinamiese stelsels benadering. Verder verskaf die studie ’n leidende proses te opsigte van die toepassing van die raamwerk tot energie tegnologie assesseringsteorie en praktyk binne die konteks van volhoubaarheidsontwikkeling. Biodiesel word gebruik vir die demonstrasie omdat dit gereken word as ’n skoner plaasvervanger vir brandstof en daar aangevoer word dat dit ’n potensiële bydraer tot volhoubaarheidsontwikkeling is. Die ontwikkeling van biodiesel behels komplekse interaksie tussen verskeie akteurs soos tegnologiese ontwikkelaars, die regering op verskillende vlakke, gemeenskappe asook die natuurlike omgewing. Verskeie aksies of reaksies in die groter sisteem mag dalk die positiewe effek van so ontwikkeling ondermyn of verhinder. ’n Biodiesel Tegnologiese Volhoubaarheidsassessering (BIOTVA) model is ontwerp gebaseer op die SBTVA raamwerk. Die BIOTVA model is gebruik om die uitkomste op geselekteerde volhoubaarheidsaanduiders van ’n voorgestelde biodiesel produksie ontwikkeling in die Oos- Kaap Provinsie van Suid-Afrika te toets. Buiten vir die voorafgaande is sekere beleidtoekomsblikke ook getoets om te vergelyk hoe hulle sal help om die geselekteerde aanwysers te verbeter. Die BIOTVA model resultate is behulpsaam in die vergelyking van dinamiese gevolge wat voortspruit uit die voorgestelde biodiesel produksie ontwikkeling asook die onderskeie beleide en besluite wat mag ontstaan van so ’n ontwikkeling. Die toetsing en bekragtiging van die BIOTVA model was uitgevoer gebaseer op strukturele geldigheid, gedragsgeldigheid, en kundige opinie. Potensiële beleidtoekomsblikke uitkomste en die nagevolge, ten opsigte van die geselekteerde volhoubaarheidsaanduiders, is ook getoets. Die opinies van die geselekteerde aandeelhouers het aangedui dat die BIOTVA model bruikbaar is om ’n beter begrip te verskaf ten opsigte van die potensiële impak wat die biodiesel ontwikkeling op geselekteerde volhoubaarheidsaanduiders in die Oos-Kaap Provinsie sal hê. As gevolg hiervan kan die SBTVA raamwerk toegepas word om die volhoubaarheid van ander herwinbare energie tegnologieë te assesseer. Buiten die voorafgaande kan stelsel dinamika ’n bruikbare en uitvoerbare dinamiese stelselbenadering vir energie tegnologie volhoubaarheidsassessering verskaf. Ten slotte, die model bouproses en transdisiplinêre aarde van die studie het gehelp om potensiële probleme wat kan voorkom tydens die biodiesel produksie ontwikkeling te identifiseer. Daarby is gapings in data en kennis ook geïdentifiseer en die aanbevelings vir verdere studie in die veld is uitgelig. Nieteenstaande kan die bevindings van die BIOTVA model beleidmakers en besluitnemers in die biodiesel produksie ontwikkeling van Suid- Afrika inlig. Die ontwikkeling van soortgelyke modelle vir ander herwinbare energie ontwikkelingspogings word aanbeveel. As voorbeeld sal die huidige pogings om die grootskaalse uitrol van gekonsentreerde son termiese tegnologieë in Suider-Afrika te fasiliteer die ontwikkeling van ’n Son Termiese Tegnologie Volhoubaarheidsassesering (SOTTVA) model benodig

Using an adapted system dynamics approach to determine the linkage between electric vehicle market penetration and affordability

CITATION: Pillay, N. S., Brent, A. C. & Musango, J. K. 2018. Using an adapted system dynamics approach to determine the linkage between electric vehicle market penetration and affordability. In SAIIE29 Proceedings, 24-26 October 2018, Spier, Stellenbosch, South Africa.The original publication is available at https://conferences.sun.ac.za/index.php/saiie29/saiie29/schedConf/presentationsThis paper focuses on an adapted process for system dynamics modelling based on industry experience and the successful implementation of system dynamics models within an electricity utility. The modelling process was demonstrated using a case study of battery electric vehicle (BEV) market penetration in South Africa and its substitution of internal combustion engine vehicle, as a function of affordability based on real disposable income. The results indicate that South Africans are living beyond their “income” constraints and purchasing far more vehicles than what their disposable income allows, with the situation worsening over time. The Gauteng province will have the largest potential to absorb BEVs (81,123) and the highest impact on residential electricity consumption (an additional 4,291 GWh) whilst the lowest is the Northern Cape province with 5,140 BEVs (an equivalent of 272 GWh). However, if disposable income is used as a parametric to determine the affordability of BEVs then there may be 80% less than the expected number of BEVs in terms of market penetration. To benefit from a reduction in carbon emissions in the transport sector, a renewables heavy supply mix would be required else there is not much benefit with South Africa’s current coal heavy supply mix.https://conferences.sun.ac.za/index.php/saiie29/saiie29/paper/view/3723Publisher's versio

Determinants of producers’ choice of wine grape cultivars in the South African wine industry

Thesis (MAgricAdmin (Agricultural Economics))--University of Stellenbosch, 2005.The wine industry is one of the oldest commercial activities in South Africa. The South African wine grape industry annually produces more than a million tonnes of grapes, making the country the ninth largest producer in the world. The total area under wine grape production is divided into eight regions for administrative purposes. These boundaries are a legacy of the era of controlled marketing and there is continued meaningfulness of having various classifications such as ‘wine of origin’ scheme. The purpose of this study is to identify the factors that determine the producers’ choice of wine grape cultivars in the wine regions in South Africa. Time series data for the period 1990-2003 were used to estimate the parameters of linear regression models. Two equations for each wine grape cultivar in each region were postulated and estimated using Ordinary Least Squares as applied with Eviews. Further, a stepwise regression as applied in STATISTICA was used to eliminate the parameters that were not statistically significant at five percent significant level. In identifying the factors that determine the choice of wine grape cultivars in the regions, the results showed that each wine grape cultivar in each region has its own factors influencing the producers’ choice of that specific wine grape cultivar. Same wine grape cultivars in different regions similarly have its own factors determining the producers’ choice. The implication of this is that there are differences in terms of the requirements and types of crops and wine grape cultivars grown in each region. However, the most important result that emerged with regular frequency is that, the factors determining the producers’ choice of a specific wine grape cultivar for each region is price of other wine grape cultivars and competitive products in that wine region. The price of specific wine grape cultivars only had an influence on few wine grape cultivars. The implication is that the producers in South Africa appears to consider the prices of other wine grape cultivars and competitive products before making a choice of whether to plant or uproot a specific wine grape cultivar more than the price of the specific wine grape cultivar. This supports the theory that farm prices play a key role in allocating resources and in rewarding efficient producers

A generic technology assessment framework for sustainable energy transitions in African contexts

DATA AVAILABILITY : No data was used for the research described in the article.How African countries manage transitions to decarbonised, environmentally and socially acceptable energy systems is a topical issue in public policy, politics and academic spheres today. There is recognition that technology assessment plays a critical role in the choice of specific pathways to just clean energy transitions. Yet, there is limited energy technology assessment practice in Africa. In fact, technology assessment is not well understood and institutionalised. This, in part, is due to the absence of Africa context tailored technology assessment frameworks. This study used an integrated literature review to explore the state and forms of technology assessments and their relevance to energy technology assessment research. The review showed that diverse forms of technology assessments have evolved due to changing priorities in policy, methodological and practical aspects. We propose an action-oriented energy technology assessment that considers geographical contexts, sustainable development dimensions, and different energy systems as dynamic and fosters inclusive stakeholder engagement. The main output of our proposal is a 3-phased generic framework for conducting energy technology assessments. We conclude that the action-oriented perspective needs to consider a transdisciplinary approach to promote sustainable energy transition and evaluate the sustainability of different energy transition technologies in systemic socio-political and energy contexts.The National Research Foundation incentive funding for rated researchers.https://www.elsevier.com/locate/techfore2025-11-18hj2024Graduate School of Technology Management (GSTM)SDG-07:Affordable and clean energ

A Systematic Review on the Application of the Living Lab Concept and Role of Stakeholders in the Energy Sector

The living lab concept is identified as having the potential to provide a platform to test technologies and support energy transition. However, the application of the concept to the energy sector is limited, though emerging. This study undertook a systematic literature review to understand the extent of the application of the living lab concept, with the particular aim of informing the processes to establish such a platform in urban Africa. Using a sample of 35 papers, only 17 papers were related to energy-living labs, while 18 papers were outside the energy field. The scale and contexts of the application of living labs were diverse. However, not all initiatives that defined themselves as living labs were characterised by elements typical of the concept of a living lab. Further, how the stakeholders were identified, and the stakeholder recruitment process in energy living labs was unclear in the sampled studies. A recommendation is to improve transparency in the stakeholder identification, engagement, and recruitment process in energy living labs and to incorporate gendered issues into the setup and management of urban energy living labs